I'm upgrading the commuter from 8 to 10 speed, wondering if anyone has experience with the compatibility of older cranksets to 10 speed? The issue would be if the chainrings on newer 10 speed specific cranksets are closer together (due to the thinner chain i guess).I'm thinking even if this is the case, i can put some spacers between one of the chainrings and the crank to move them closer together.

I am running a 9speed set up with new Ultegra rings on 7400 Series Dura Ace cranks - they look very similar to the 6200 Series 600/Ultegra cranks. I am running the 7400 Series FD with it as well and that dates from around the 6/7 speed era. I think there's a little bit more trimming involved because the older FD cage being designed for a fatter chain, but it's not really an issue.

I wanted to run the nice 7400 RD at the back, but because it dates back to the narrow 126mm spacing days and only 6/7 speed - it lacks the throw range to quite reach the lowest sprocket.

Have a dust up read of Sheldon's general gear compatibility article. I think you find you'll be right.

I'm thinking even if this is the case, i can put some spacers between one of the chainrings and the crank to move them closer together.

i'm not staring at my bike right now, but from memory (which is hazy at best), the chainrings mount on the frame side of the cranks, so if i needed the chainrings slightly closer together, i could put some thin spacers in between the large chainring and the cranks, which would effectively move the large chainring closer to the small so the gap was reduced. This would only matter if the 10 speed FD range was marginally smaller than 8 speed. Like i said, I don't even know if this is an issue.

I've already done it, new Ultera 10 speed gear on an older 6 speed, 600 Shimano Durace cranks, Just needed the new chain rings, and a bit of fiddling around with the front derailuer and away i went, was more of a problem sorting out the rear with the new RD but doable, but what do i do with all those extra gears now!

the large chainring screws down on the pedal side of the cranks, and the small chainring on the bike side, so adding spacers would only add to the distance between the 2.. would need to grind out the mounting points for the chainrings a bit on the cranks to get them closer. what i meant was if they both mounted to the cranks on the same side of the cranks, you could put a spacer in between the large chainring and the place where it sits against the cranks before screwing it down to lift it off the cranks a little, moving it closer to the small chainring.. urgh, anyway it's not relevant now.

The tactile stuff i have in front of me at present are about 5 files, a notebook, keyboard and mouse.. I'm "multitasking".Have to wait for the derailleur's to arrive before i can get started, hopefully tomorrow in time for the weekend.

That's a great effort, nice work!No, my record to date is 160km's, did 130 or so a couple of weeks ago, Newtown to Kiama. Might try Newtown to Newcastle next, sussing out roads that aren't full off hoons first.

Yeah, i figured the FD's are pretty cheap, and i'll sell the 600 Sti brifters with the front and rear mech's, good to keep them together if someone's looking to build a bike with an older groupset. actually the FD's 105 and the rear's Ultegra, so bit of a mixed bag.

This is my lightweight steel roady. I've been doing the bigger Ks on the Surly Crosscheck with 35mm tyres. Heavy, comfy and able to to carry some supplies. Though the hardcore more experienced Audax riders inspire me with their quite lean setups. I'm enjoying pushing my limits and learning how much less I need to carry on some of the shorter rides. Will probably be doing 150km/100miles on the Miyata before too long if I continue at my present rate.

- KymProud to have been a regular during BNA's heyday. I'm still reachable by PM (email alerts) - dec 2016

Had a pretty busy weekend, but managed to make some time last night to install the 10 speed gear.

Having an issue with the fd that has me stumped, it doesn't have enough range to change to the small ring (this is a double setup).I've undone the limit screws, and even with the fd cable unattached, it wont even let the outside bar of the fd cage get in line with the big ring or go past it to the small ring side, the inner range has it sitting outside. So basically i can't get the chain to come off the big ring, unless i manually push on the fd to bend/flex it a bit it will just pop off, but then i have the issue where it's rubbing on the fd even on the big cog..

I thought maybe the fd was bent, but it looks pretty straight, the chainline is 41mm for the small ring and 46mm for the large, which corresponds with Sheldon's chainline guide for a Shimano road double.

If i hold the older RX100 FD i had on the bike previously over the top of the 105 fd, it seems to have more range on the small ring side than the 105.I can't think what can be going on, unless there's something stuck in the fd, but i had a pretty good look at it.. annoying as i've connected the chain already (shimano).

I'm upgrading the commuter from 8 to 10 speed, wondering if anyone has experience with the compatibility of older cranksets to 10 speed? The issue would be if the chainrings on newer 10 speed specific cranksets are closer together (due to the thinner chain i guess).I'm thinking even if this is the case, i can put some spacers between one of the chainrings and the crank to move them closer together.

Not sure if this is even an issue though..

You are on the money. The older chain rings have a different "offset", resulting in a wider space between them. I have tried them with a 10 speed chain, and when changing down to the smaller chain ring, the chain sits between the two rings and I hit "neutral" gear. To get onto the small ring, I have to move the rear to the biggest cog, and this change in chain angle encourages the chain to the small front ring. Why do I put up with this? It is the training bike, and I am using up old gear.

Ok I've been doing lots of reading. I'm in a very similar situation. I have a bike with Shimano 600 Ultegra 8-speed drivetrain. The chain rings are bent, and buying some 2nd-hand chainrings from bicycle recycle didn't really improve the situation. Having bent rings does make it difficult to tune the front derailleur position as you often get chain rub where you shouldn't.

Getting good new 8-speed chainrings seems almost impossible. But there are plenty of good quality new 9-speed rings still around.

Now various people on the web will tell you various things. Sheldon Brown says the following about moving from 8 to 9-speed rings here

Sheldon Brown wrote:When the move from 8- to 9-speed took place, starting with 1997 Dura-Ace, a very slight change in chainring design occurred. Shimano was concerned about the potential for the chain to "skate" over the teeth of the small chainring.

"Skating" occurs when a narrow chain is used on a crankset intended for a somewhat wider chain. In downshifting, instead of the chain meshing properly with the teeth of the inner chainring, the side-plates of the chain can ride along the tips of the teeth of the small ring, causing a momentary "freewheeling" forward. If you are foolish enough to downshift the front while standing up, this skating could conceivably cause you to crash.

The difference between "9-speed" cranksets and older models is only in the inner chainring. The teeth on a "9-speed" inner ring are slightly displaced to the right to better accommodate the slightly narrower chain.

Shimano will tell you you need to replace the inner ring when converting an older bike to 9-speed. Their lawyers say that covers them if you're clumsy enough to hurt yourself due to "skating" and, besides, they make a nice profit selling the chainrings.

My advice is to not worry about this, and not to routinely replace the inner ring when upgrading to 9-speed. This type of "skating" is very rare, and mostly only happens if you're in top gear front and rear, then decide to downshift the front before downshifting the rear. There's no situation where this is a rational shifting sequence anyway.

Sheldon Brown wrote:Old Chainrings, New ChainsThere is a lot of confusion about the compatibility of narrow 9- and 10-speed chains with older cranksets. Shimano says you should replace the inner chainring(s) with specially designated 9- or 10-speed ones, but then they're all too eager to sell you stuff, whether you need it or not.

These chainrings have the teeth slightly farther to the right than the older chainrings to work a little better with the narrower chains. There is no difference whatever in the crank spiders.

The manufacturers also are concerned about clueless users. The worst-case scenario is that you will be riding along with the bike in its highest gear (large front, small rear) and then for some bizarre reason shift down in front before downshifting in the back. (There is no shift pattern in which it is reasonable to shift in this sequence.) [Not with a 9- or 10-speed cassette, to be sure -- John Allen] If you do shift this way, there's a small chance that the chain might "skate" over the edges of the teeth for maybe half a turn.

In practice this "problem" almost never materializes. Many, many cyclists are using 9- and 10-speed chains with older cranksets and having no problems whatever.New Chainrings, Old ChainsGoing the other direction, using wider chains with chainrings intended for narrower chains is not generally a major problem if there's only a one- or two- generation difference. The only problem you might run into is that the chain will be more liable to rub on the inside of the bigger chainrings in the small/small crossover gears, gears you shouldn't be using in any case.

This suggests that running an 8-speed chain on 9-speed chainrings is prefectly fine. However two posters on this mountain bike forum have stated in response to the following claims by Sheldon Brown that:

Someone on a mountain bike forum wrote:No No No, run the nine speed chain with the nine speed cranks, other wize you end up getting chain suck too easily. the nine speed chain works just fine on an eight sped cassette.

Someone else wrote:The width of the two chains is seriously different, the 8spd. chain will float sise to side creating nast wear, while the 9spd chain will work on the cranks and cass. fine. Trust me and mike on this dont do it unless you are stranded and dont have an option

Shimano OE replacement Dura Ace 7800 39T/42T inner ring. Works perfectly when mated to a 7800 outer ring, but will work with any 130mm bolt crankset and 8, 9 or 10 speed drivetrain. Cut from straight block alloy, then profiled and polished to that high luster you expect from Dura-Ace. Not recommended for a single ring front(cross or fixed gear because of the tooth profiling).

I suppose I could try 9 speed chainrings first while keeping my 8 speed chain. If there is significant chain rub, then buy a 9-speed chain.

At some point this bike will get a re-spray and a full new groupset, but I'm just trying to keep it on the road for now (have already spend too much $$$'s on new bike which is coming later in the year).

At first glance _PG_ your front derailler is way too high. Bring it down so that the outer plate is only 1-2mm above the teeth of the big ring at its closest. (This assumes they are not Biopace or similar non-circular rings)

Then make sure that outer plate is parallel with the plane of the rings.

There will be always someone that will have had a problem with different combos. As I said earlier, I run mine with a 10sp chain with no problems at all and this is a crank set from the late 70s and another with a full Shimano bike from early 80s.

Foo

I don't suffer fools easily and so long as you have done your best,you should have no regrets.Goal 6000km

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